Question

我有一个表输出如下：

class | student | week | eng |  maths | science
  1   |   stu1  |   1  | 67  |   78   |     89
  1   |   stu2  |   1  | 78  |   88   |     90
  1   |   stu3  |   1  | 45  |   34   |     45
  1   |   stu1  |   2  | 67  |   45   |     34

我需要最终输出：

class | student |   sub   |  week1 |    week2
  1   |   stu1  |   eng   |     67 |    67
  1   |   stu1  |   maths |     78 |    45
  1   |   stu1  | science |     89 |    34
  1   |   stu2  |   eng   |     78 |    89
  1   |   stu2  |   maths |     88 |    90
  1   |   stu2  | science |     90 |    89
  1   |   stu3  |   eng   |     45 |    
  1   |   stu3  |   maths |     34 |    
  1   |   stu3  | science |     45 |

在表中，只有一部分，行被转换为列，列被转换为行。

我正在使用oracle 10g。

这是我对第一张表的查询。

select class, student,
to_char(dt,'WW') as week,
sum(case when sm.sub='eng' then 'eng' end) as eng,
sum(case when sm.sub='maths' then 'maths' end) as maths,
sum(case when sm.sub='science' then 'science' end) as science
from studentList sl left join studentMarks sm
on sl.stId=sm.stId
group by class, student, to_char(dt,'WW')
order by class, student;

Answer 1

使用PIVOT / UNPIVOT运算符。请在这里找到一篇好文章： https://technet.microsoft.com/en-us/library/ms177410(v=sql.105).aspx

对于oracle 10g中的表的一部分，将行转换为列，反之亦然

1 个答案: